xds: fix wrong json key balancerName
diff --git a/xds/src/main/java/io/grpc/xds/XdsNameResolver.java b/xds/src/main/java/io/grpc/xds/XdsNameResolver.java
index 8823eff..9ac6d10 100644
--- a/xds/src/main/java/io/grpc/xds/XdsNameResolver.java
+++ b/xds/src/main/java/io/grpc/xds/XdsNameResolver.java
@@ -83,7 +83,7 @@
       serviceConfig = "{"
           + "\"loadBalancingConfig\": ["
           + "{\"xds_experimental\" : {"
-          + "\"balancer_name\" : \"" + serverUri + "\","
+          + "\"balancerName\" : \"" + serverUri + "\","
           + "\"childPolicy\" : [{\"round_robin\" : {}}]"
           + "}}"
           + "]}";
diff --git a/xds/src/test/java/io/grpc/xds/XdsNamResolverTest.java b/xds/src/test/java/io/grpc/xds/XdsNamResolverTest.java
index f22b619..02a5cdd 100644
--- a/xds/src/test/java/io/grpc/xds/XdsNamResolverTest.java
+++ b/xds/src/test/java/io/grpc/xds/XdsNamResolverTest.java
@@ -173,7 +173,7 @@
     Map<String, ?> rawConfigValues = (Map<String, ?>) xdsLbConfig.get("xds_experimental");
     assertThat(rawConfigValues)
         .containsExactly(
-            "balancer_name",
+            "balancerName",
             "fake_server_uri",
             "childPolicy",
             Collections.singletonList(